While significant advances have been achieved in the field of contact lens design and fabrication, many problems still exist. Paramount of these is the fact that it is common for a contact lens to be constructed as a completely homogenous solid or with a homogenous outer surface enclosing a hydrogel or polymeric interior, which means that the lens outer covering material is consistent throughout its structure. These structures reduce the available oxygen to the corneal surface, minimize tear and aqueous transport through the lens, and act as a nucleation point for protein buildup.
Electrospun polymer fibers provide a material with a variety of favorable characteristics that may be tailored to fit various applications. It is therefore desirable to provide an ophthalmic drug delivery system utilizing electrospun polymer fibers. The system may utilize an improved contact lens incorporating electrospun fibers with desired characteristics, and a system and method for delivering ophthalmic drugs from the improved contact lens to an eye over an extended period of time while maintaining the concentration of the drug in the eye at an efficacious level throughout the period of drug delivery.
A number of patents disclose the use of electrospun fibers for ocular adaptation or treatment. For example, U.S. Pat. No. 7,563,396 discloses a technique for creating polymer fibril diameters and spacing that duplicate the optical transmission and diffusion characteristics of natural corneal collagen; U.S. Pat. No. 8,083,347 discloses methods of coating and cross-linking polymer fibers in contact lenses; and U.S. Pat. No. 8,361,492 discloses drug-delivery systems, both through direct use of electrospun fibers in the eye and by inclusion of the fibers in a contact lens.